Hi Ariel! That screen looks like a Servo-U to me, one of the ventilators we use in our ICU. The waveform display appears to show two manoeuvres used to assess inspiratory effort:
— End-inspiratory occlusion: Pplat close to 40 cmH₂O and an estimated PMI of approximately 4 cmH₂O.
— End-expiratory occlusion: ΔPocc close to 8 cmH₂O, corresponding to an estimated Pmus of approximately 6 cmH₂O, with the usual limitations of this method.
Taken together, these findings neither establish nor rule out readiness for extubation. The estimated Pmus suggests a moderate inspiratory effort under the current level of support. Neither finding would, by itself, preclude carefully monitored extubation if all other clinical criteria were met, but neither would be sufficient to justify proceeding.
An SBT performed while maintaining a PEEP of 28 cmH₂O would not be a conventional liberation trial and would not tell us how much effort the patient would generate without positive pressure. It would only show that the patient can breathe spontaneously while remaining substantially unloaded. However, if the plan were to extubate directly to NIV, I would not necessarily require the patient to tolerate complete withdrawal of positive pressure for a prolonged period.
I would assess respiratory rate, tidal volume expressed relative to predicted body weight, thoracoabdominal breathing pattern, accessory muscle use, dyspnoea, blood gases, haemodynamics, cough strength, secretion burden, and the ability to protect the airway. The fact that the patient can communicate in writing indicates that they are awake and cooperative, but it does not exclude increased work of breathing. I do not see enough information in the screenshot to conclude that the patient has overt respiratory distress; moreover, the effort shown here was assessed while the patient was receiving PEEP 28 cmH₂O and pressure support 6 cmH₂O.
If the patient otherwise met extubation criteria, I would favour extubation directly to NIV, given the morbid obesity and the high level of positive pressure currently required. Before extubation, I would briefly assess the response to substantially lower support and progressively reduce invasive PEEP to identify a level at which the patient maintains adequate oxygenation and ventilation without a clinically relevant increase in inspiratory effort or evidence of derecruitment. I would not necessarily require a prolonged zero-support or T-piece trial.
For post-extubation NIV, if previous effective home settings were available, I would use them as a reference rather than as a fixed prescription. If no previous settings were available, I would individualise EPAP according to the response observed during invasive PEEP reduction and after extubation, rather than automatically transferring the invasive PEEP level to the mask. I would increase EPAP if desaturation, evidence of derecruitment, upper-airway obstruction, or increased respiratory effort developed, and subsequently reduce it as the acute component resolved.
I would titrate pressure support according to inspiratory effort, respiratory rate, tidal volume, PaCO₂, pH, and patient–ventilator synchrony. If the patient genuinely required an expiratory pressure close to 28 cmH₂O to remain clinically stable, and this could not be delivered safely and effectively through NIV, I would reconsider whether the patient was ready for extubation.